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Yury N. Razoumny - One of the best experts on this subject based on the ideXlab platform.
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fundamentals of the route theory for Satellite Constellation design for earth discontinuous coverage part 4 compound Satellite structures on orbits with synchronized nodal regression
Acta Astronautica, 2016Co-Authors: Yury N. RazoumnyAbstract:Abstract Basing on the theory results considered in the previous papers of the series for traditional one-tiered Constellation formed on the orbits with the same values of altitudes and inclinations for all the Satellites of the Constellation, the method for Constellation design using compound Satellite structures on orbits with different altitudes and inclinations and synchronized nodal regression is developed. Compound, multi-tiered, Satellite structures (Constellations) are based on orbits with different values of altitude and inclination providing nodal regression synchronization. It is shown that using compound Satellite Constellations for Earth periodic coverage makes it possible to sufficiently improve the Earth coverage, as compared to the traditional Constellations based on the orbits with common altitude and inclination for all the Satellites of the Constellation, and, as a consequence, to get new opportunities for the Satellite Constellation design for different types of prospective space systems regarding increasing the quality of observations or minimization of the number of the Satellites required.
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fundamentals of the route theory for Satellite Constellation design for earth discontinuous coverage part 2 synthesis of Satellite orbits and Constellations
Acta Astronautica, 2016Co-Authors: Yury N. RazoumnyAbstract:Abstract The method for synthesis of Satellite orbits and Constellations, optimized by given criterion (minimum of required number of Satellites in the Constellation, or minimum revisit time, or minimum of the Satellites' swath width required) for fixed parameters of on-board Satellite equipment and constraints for unused criterion parameters of a list of mentioned above is presented. The numerical results demonstrate the possibilities of the method developed basing on analyzing the given Satellite Constellation revisit time values distributed on the Earth coverage area, and for synthesizing the Satellite Constellations to minimize revisit time in comparison with the traditional approaches based on Constellation design in a priori fixed classes used for continuous coverage. Particularly, it is shown that the suggested synthesis method, basing on the simplest type of Route Constellations considered – Secure Route Constellations, directly leads, as result of high speed calculations for given Earth region coverage (seconds, or minutes as a worst case), to the optimized Satellite Constellations which provide consistently high performance and are better, or at least on the same level, in comparison with the best Walker Constellations for discontinuous coverage. In order to have comprehensive coverage picture, both deterministic, and stochastic approaches are considered for estimation of the coverage characteristics of the given region of arbitrary shape, basing on the results of Earth coverage analytic emulation.
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fundamentals of the route theory for Satellite Constellation design for earth discontinuous coverage part 1 analytic emulation of the earth coverage
Acta Astronautica, 2016Co-Authors: Yury N. RazoumnyAbstract:Abstract This paper opens a series of articles expounding the fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. In Part 1 of the series the analytical model for Earth coverage by Satellites’ swath conforming to the essential of discontinuous coverage, in contrast to continuous coverage, is presented. The analytic relations are consecutively derived for calculation of single- and multi-Satellite Earth surface latitude coverage as well as for generating full set of typical Satellite visibility zone time streams realized in the repeating latitude coverage pattern for given arbitrary Satellite Constellation. The analytic relations mentioned are used for developing the method for analysis of discontinuous coverage of fixed arbitrary Earth region for given Satellite Constellation using both deterministic and stochastic approaches. The method provides analysis of the revisit time for given Satellite Constellation, as a result of high speed (fractions of a second or seconds) computer calculations in a wide range of possible revisit time variations for different practical purposes with high accuracy which is at least on par with that provided by known numerical simulating methods based on direct modeling of the Satellite observation mission, or in a number of cases is even superior to it.
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Fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. Part 3: Low-cost Earth observation with minimal Satellite swath☆
Acta Astronautica, 2016Co-Authors: Yury N. RazoumnyAbstract:Abstract Continuing the series of papers with description of the fundamentals of the Route Theory for Satellite Constellation design, the general method for minimization of the Satellite swath width required under given constraint on the maximum revisit time (MRT), the main quality characteristic of the Satellite Constellation discontinuous coverage, is presented. The interrelation between MRT and multiplicity of the periodic coverage – the minimum number of the observation sessions realized for the points of observation region during the Satellite tracks’ repetition period – is revealed and described. In particular, it is shown that a change of MRT can occur only at points of coverage multiplicity changing. Basic elements of multifold Earth coverage theory are presented and used for obtaining analytical relations for the minimum swath width providing given multifold coverage. The Satellite swath width calculation procedure for the multifold coverage of rotating Earth using the iterations on the sphere of stationary coverage is developed. The numerical results for discontinuous coverage with minimal Satellite swath, including comparison with some known particular cases and implementations of the method, are presented.
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analytic solutions for earth discontinuous coverage and methods for analysis and synthesis of Satellite orbits and Constellations
AIAA AAS Astrodynamics Specialist Conference, 2014Co-Authors: Yury N. RazoumnyAbstract:The analytical model for Earth coverage by the Satellites’ swath conforming to essential of discontinuous coverage, in contrast to continuous coverage, is presented. The analytic relations are consecutively derived for calculation of singleand multi-Satellite Earth surface latitude coverage as well as for generating full set of typical Satellite visibility zone time streams realized in the repeating latitude coverage pattern for given arbitrary Satellite Constellation. The analytic relations mentioned are used for developing the method for analysis of discontinuous coverage of fixed arbitrary Earth region for given Satellite Constellation using both deterministic and stochastic approaches. The method provides analysis of the revisit time for given Satellite Constellation, as a result of high speed (fractions of a second or seconds) computer calculations in a wide range of possible revisit time variations for different practical purposes with high accuracy which is at least on par with that provided by known numerical simulating methods, based on direct modelling of the Satellite observation mission, or in a number of cases is even superior to it (due to the fact that when using the analytic procedures observation sessions cannot be missed). The method for synthesis of Satellite orbits and Constellations, optimized by given criterion (minimum of required number of Satellites in the Constellation, or minimum revisit time, or minimum of the Satellites’ swath width required) for fixed parameters of on-board Satellite equipment and constraints for unused criterion parameters of a list of mentioned above is presented. The numerical results demonstrate the possibilities of the methods developed for analyzing the given Satellite Constellation revisit time values distributed on the fixed Earth coverage area, and for synthesizing the Satellite Constellations in comparison with the traditional approaches based on Constellation design in a priori fixed classes used for continuous coverage. Particularly, it is shown that the suggested method for synthesis of Secure Route Constellations, using deterministic and stochastic basis, directly leads to the optimized Satellite Constellations which provide consistently high performance and are at least on the same level, or better, in comparison with the best Walker Constellations for discontinuous coverage.
Razoumny Y.n. - One of the best experts on this subject based on the ideXlab platform.
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New research methodology for earth periodic coverage and regularities in parametric localization of optimal low-earth-orbit Satellite Constellations
Univelt Inc., 2020Co-Authors: Razoumny Y.n.Abstract:The way to solve the problem of Satellite Constellation design was outlined in the 1960s on recognizing the importance of Satellite coverage (continuous or periodic) function allowing interpreting the operation of different types of space systems. Due to the fact that Earth periodic coverage optimization is extremely complex, for many years the solutions of this problem have been searched for among a priori fixed Constellation types successfully implemented before for continuous coverage, with continuous coverage seeming to be much easier than the periodic one. In this study, it is shown that the technological advance in Satellite Constellation design for periodic coverage could be achieved considering it as a unique and separate problem. The new research methodology for Earth periodic coverage aiming on creating methods for optimization arbitrary Constellations, alternatively to traditional approach considering narrow classes of Constellations to be analyzed, is described. The unknown before regularities in Earth periodic coverage and localization of optimal low-Earth-orbit Satellite Constellations parameters are presented and illustrated
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Fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. Part 3: Low-cost Earth observation with minimal Satellite swath
'Elsevier BV', 2020Co-Authors: Razoumny Y.n.Abstract:Continuing the series of papers with description of the fundamentals of the Route Theory for Satellite Constellation design, the general method for minimization of the Satellite swath width required under given constraint on the maximum revisit time (MRT), the main quality characteristic of the Satellite Constellation discontinuous coverage, is presented. The interrelation between MRT and multiplicity of the periodic coverage - the minimum number of the observation sessions realized for the points of observation region during the Satellite tracks' repetition period - is revealed and described. In particular, it is shown that a change of MRT can occur only at points of coverage multiplicity changing. Basic elements of multifold Earth coverage theory are presented and used for obtaining analytical relations for the minimum swath width providing given multifold coverage. The Satellite swath width calculation procedure for the multifold coverage of rotating Earth using the iterations on the sphere of stationary coverage is developed. The numerical results for discontinuous coverage with minimal Satellite swath, including comparison with some known particular cases and implementations of the method, are presented. (C) 2016 IAA. Published by Elsevier Ltd. All rights reserved
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Analytic solutions for earth discontinuous coverage and methods for analysis and synthesis of Satellite orbits and Constellations
American Institute of Aeronautics and Astronautics Inc., 2020Co-Authors: Razoumny Y.n.Abstract:The analytical model for Earth coverage by the Satellites' swath conforming to essential of discontinuous coverage, in contrast to continuous coverage, is presented. The analytic relations are consecutively derived for calculation of single- and multi-Satellite Earth surface latitude coverage as well as for generating full set of typical Satellite visibility zone time streams realized on the latitude points for given arbitrary Satellite Constellation. The analytic relations mentioned are used for developing the method for analysis of discontinuous coverage of fixed arbitrary Earth region for given Satellite Constellation using both deterministic and stochastic approaches. The method provides analysis of the revisit time for given Satellite Constellation, as a result of high speed (fractions of a seconds or seconds) computer calculations with high accuracy and in wide range of possible variations of this parameter. The method for synthesis of Satellite orbits and Constellations, optimized by given criterion (minimum of number of Satellites in the Constellation, or minimum revisit time, or minimum of the required width of the Satellite swath) for fixed parameters of on-board Satellite equipment and constraints for unused criterion parameters of a list of mentioned above is presented. The numerical results demonstrate the possibilities of the methods developed for analyzing the given Satellite Constellation revisit time values distributed on the fixed Earth coverage area, and for synthesizing the Satellite Constellations in comparison with the traditional approaches based on Constellation design in a priori fixed classes used for continuous coverage. Particularly, it is shown that the suggested method for synthesis of Secure Route Constellations, using determenistic and stochastic basis, leads to the optimized Satellite Constellations which provide consistently high performance and are at least on the same level, or better, in comparison with the best Walker Constellations for discontinuous coverage
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Fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. Part 2: Synthesis of Satellite orbits and Constellations
'Elsevier BV', 2020Co-Authors: Razoumny Y.n.Abstract:The method for synthesis of Satellite orbits and Constellations, optimized by given criterion (minimum of required number of Satellites in the Constellation, or minimum revisit time, or minimum of the Satellites' swath width required) for fixed parameters of on-board Satellite equipment and constraints for unused criterion parameters of a list of mentioned above is presented. The numerical results demonstrate the possibilities of the method developed basing on analyzing the given Satellite Constellation revisit time values distributed on the Earth coverage area, and for synthesizing the Satellite Constellations to minimize revisit time in comparison with the traditional approaches based on Constellation design in a priori fixed classes used for continuous coverage. Particularly, it is shown that the suggested synthesis method, basing on the simplest type of Route Constellations considered Secure Route Constellations, directly leads, as result of high speed calculations for given Earth region coverage (seconds, or minutes as a worst case), to the optimized Satellite Constellations which provide consistently high performance and are better, or at least on the same level, in comparison with the best Walker Constellations for discontinuous coverage. In order to have comprehensive coverage picture, both deterministic, and stochastic approaches are considered for estimation of the coverage characteristics of the given region of arbitrary shape, basing on the results of Earth coverage analytic emulation. (C) 2016 IAA. Published by Elsevier Ltd. All rights reserved
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Fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. Part 1: Analytic emulation of the Earth coverage
'Elsevier BV', 2020Co-Authors: Razoumny Y.n.Abstract:This paper opens a series of articles expounding the fundamentals of the route theory for Satellite Constellation design for Earth discontinuous coverage. In Part 1 of the series the analytical model for Earth coverage by Satellites' swath conforming to the essential of discontinuous coverage, in contrast to continuous coverage, is presented. The analytic relations are consecutively derived for calculation of single- and multi-Satellite Earth surface latitude coverage as well as for generating full set of typical Satellite visibility zone time streams realized in the repeating latitude coverage pattern for given arbitrary Satellite Constellation. The analytic relations mentioned are used for developing the method for analysis of discontinuous coverage of fixed arbitrary Earth region for given Satellite Constellation using both deterministic and stochastic approaches. The method provides analysis of the revisit time for given Satellite Constellation, as a result of high speed (fractions of a second or seconds) computer calculations in a wide range of possible revisit time variations for different practical purposes with high accuracy which is at least on par with that provided by known numerical simulating methods based on direct modeling of the Satellite observation mission, or in a number of cases is even superior to it. (C) 2016 IAA. Published by Elsevier Ltd. All rights reserved
Peter J. G. Teunissen - One of the best experts on this subject based on the ideXlab platform.
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Australia-first high-precision positioning results with new Japanese QZSS regional Satellite system
GPS Solutions, 2018Co-Authors: Safoora Zaminpardaz, Kan Wang, Peter J. G. TeunissenAbstract:The Japanese Quasi-Zenith Satellite System (QZSS) has recently (October 2017) reached its first 4-Satellite Constellation. In this contribution, the standalone performance of this 4-Satellite QZSS Constellation is assessed by means of its triple-frequency (L1 + L2 + L5) real-time kinematic (RTK) integer ambiguity resolution and precise positioning capabilities. Our analyses are carried out for data collected in Perth, Australia, and include a study of the noise characteristics of the QZSS code and phase data, particularly concerning their precision, time correlation and multipath. Our results show that while the phase observations on different frequencies are of similar precision, the code observations on different frequencies show considerably different precisions and can be ordered, from high to low, as L5, L2 and L1. As to positioning and ambiguity resolution, we demonstrate that the Position Dilution Of Precision (PDOP) and the Ambiguity Dilution Of Precision (ADOP) exhibit complementary characteristics, both of which are important for predicting precise positioning capabilities. We show that despite the large PDOPs, the ADOPs are sufficiently small to indicate (almost) instantaneous successful ambiguity resolution. This is confirmed by our empirical data analyses, demonstrating that instantaneous ambiguity resolution is feasible, despite the relatively poor 4-Satellite receiver-to-Satellite positioning geometry over Australia, thus showing that already now centimeter-level stand-alone QZSS positioning is possible with the current 4-Satellite Constellation (February–March 2018).
Tong Xudong - One of the best experts on this subject based on the ideXlab platform.
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Overview of China Earth Observation Satellite Programs [Space Agencies]
IEEE Geoscience and Remote Sensing Magazine, 2015Co-Authors: Gu Xingfa, Tong XudongAbstract:China has developed some Satellite series such as meteorological Satellite series Fengyun (FY), ocean Satellite series Haiyang (HY), Earth resources Satellite series Ziyuan (ZY), environment and disaster monitoring small Satellite Constellation (HJ), as well as Shijian Satellite series (SJ) for new technological experiments, and has formed a complete Earth observation Satellite and ground application system. Until now, 20 Chinese Earth observation Satellites have been launched. Chinese Earth observation system has not only largely contributed to the rapid economic development of China, but also become a crucial part of international Earth observation system.
Shoji Yoshikawa - One of the best experts on this subject based on the ideXlab platform.
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Satellite Constellation pattern optimization for complex regional coverage
Journal of Spacecraft and Rockets, 2020Co-Authors: Hang Woon Lee, Seiichi Shimizu, Shoji YoshikawaAbstract:The use of regional-coverage Satellite Constellations is on the rise, urging the need for an optimal Constellation design method for complex regional coverage. Traditional Constellations are often ...
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Satellite Constellation pattern optimization for complex regional coverage
arXiv: Optimization and Control, 2019Co-Authors: Hang Woon Lee, Seiichi Shimizu, Shoji YoshikawaAbstract:The use of regional coverage Satellite Constellations is on the rise, urging the need for an optimal Constellation design method for complex regional coverage. Traditional Constellations are often designed for continuous global coverage, and the few existing regional Constellation design methods lead to suboptimal solutions for periodically time-varying or spatially-varying regional coverage requirements. This paper introduces a new general approach to design an optimal Constellation pattern that satisfies such complex regional coverage requirements. To this end, the circular convolution nature of the repeating ground track orbit and common ground track Constellation is formalized. This formulation enables a scalable Constellation pattern analysis for multiple target areas and with multiple sub-Constellations. The formalized circular convolution relationship is first used to derive a baseline Constellation pattern design method with the conventional assumption of symmetry. Next, a novel method based on binary integer linear programming is developed, which aims to optimally design a Constellation pattern with the minimum number of Satellites. This binary integer linear programming method is shown to achieve optimal Constellation patterns for general problem settings that the baseline method cannot achieve. Five illustrative examples are analyzed to demonstrate the value of the proposed new approach.
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optimization of Satellite Constellation deployment strategy considering uncertain areas of interest
Acta Astronautica, 2018Co-Authors: Hang Woon Lee, Pauline C M Jakob, Seiichi Shimizu, Shoji YoshikawaAbstract:Abstract This paper presents an integrated framework to design a flexible multi-stage telecommunication Satellite configuration deployment strategy considering the uncertainties in the evolution of the areas of interest over time. The constructed stochastic demand model considers multiple possible scenarios for the evolution of the areas of interest with probabilities based on the market share growth in each area. The optimization aims to find each stage's design with minimum expected lifecycle cost considering all possible scenarios. Each stage of the Constellation, assumed to be Flower Constellation with circular orbits, provides a regional coverage of the current area of interest as well as additional coverage for the potential future areas of interest. The proposed multi-stage Satellite Constellation enables the Constellation designer to react flexibly and efficiently to the uncertain future expansion of the areas of interest. A case study reveals a reduction in the expected lifecycle cost for an optimized system compared with the all-in-single-stage system and global coverage Constellation.
